docs: def enable_cache(self):
          """Enable client-side caching for the current request"""
          self.set_header('Cache-Control', 'max-age=%d, public' % CACHE_TIME)
  
          d = datetime.datetime.now() + datetime.timedelta(seconds=CACHE_TIME)
          self.set_header('Expires', d.strftime('%a, %d %b %Y %H:%M:%S'))
  
          self.set_header('access-control-max-age', CACHE_TIME)